Binomial Theorem T AS Level Math (9709) e 1 The coefficients of x2 and x3 in the expansion of 3 − 2x6 are a and b respectively. Find the value of a . [4] b ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ 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A 1 5 (i) Find the coefficient of x in the expansion of 2x − . x [2] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ 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(ii) Hence find the coefficient of x in the expansion of 1 + 3x2 2x − x [4] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2017 9709/12/M/J/17 2 3 The coefficients of x and x2 in the expansion of 2 + ax7 are equal. Find the value of the non-zero constant a. [3] ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ © UCLES 2017 9709/13/M/J/17 2 @ 4 1 Find the term independent of x in the expansion of 2x − 2 4x A9 . 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................................................................................................................................................................ © UCLES 2017 9709/12/O/N/17 4 @ 5 A6 2 (i) Find the term independent of x in the expansion of − 3x . x [2] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ 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(ii) Find the value of a for which there is no term independent of x in the expansion of @ A6 2 1 + ax2 − 3x . x [3] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2017 9709/13/O/N/17 3 6 (i) Find the coefficients of x2 and x3 in the expansion of 1 − 2x7 . 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(ii) Hence find the coefficient of x3 in the expansion of 2 + 5x 1 − 2x7 . [2] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2018 9709/12/F/M/18 [Turn over 3 7 (i) Find the first three terms in the expansion, in ascending powers of x, of 1 − 2x5 . 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(ii) Given that the coefficient of x2 in the expansion of 1 + ax + 2x2 1 − 2x5 is 12, find the value of the constant a. [3] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2018 9709/11/M/J/18 [Turn over 2 8 0 x 16 The coefficient of x2 in the expansion of 2 + + a + x5 is 330. Find the value of the constant a. 2 [5] ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ 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................................................................................................................................................................ © UCLES 2018 9709/12/M/J/18 3 9 @ A 2 5 1 Find the coefficient of in the expansion of x − . x x [3] ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ 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................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ © UCLES 2018 9709/13/M/J/18 [Turn over 2 10 @ A 1 2 7 Find the coefficient of 2 in the expansion of 3x + 2 . x 3x [4] ................................................................................................................................................................ ................................................................................................................................................................ 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................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ © UCLES 2018 9709/12/O/N/18 2 11 @ A 1 2 7 Find the coefficient of 3 in the expansion of x − . x x [3] 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................................................................................................................................................................ © UCLES 2018 9709/13/O/N/18 3 12 The coefficient of x3 in the expansion of 1 − px5 is −2160. Find the value of the constant p. [3] ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ © UCLES 2019 9709/12/F/M/19 [Turn over 3 13 @ A k 6 The term independent of x in the expansion of 2x + , where k is a constant, is 540. x (i) Find the value of k. 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(ii) For this value of k, find the coefficient of x2 in the expansion. 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........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2019 9709/11/M/J/19 [Turn over 2 @ 14 A5 2 Find the coefficient of x in the expansion of − 3x . x [3] ................................................................................................................................................................ 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A 1 5 (i) In the binomial expansion of 2x − , the first three terms are 32x5 − 40x3 + 20x. Find the 2x remaining three terms of the expansion. 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A @ 1 5 . (ii) Hence find the coefficient of x in the expansion of 1 + 4x2 2x − 2x [2] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2019 9709/13/M/J/19 [Turn over 2 @ 16 1 Find the term independent of x in the expansion of 2x + 2 4x A6 . [3] ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ © UCLES 2019 9709/11/O/N/19 3 17 @ A x 6 The coefficient of x in the expansion of 4 + ax 1 + is 3. Find the value of the constant a. [4] 2 2 ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ © UCLES 2019 9709/12/O/N/19 [Turn over 2 18 (i) Expand 1 + y6 in ascending powers of y as far as the term in y2 . [1] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ 6 (ii) In the expansion of 1 + px − 2x2 the coefficient of x2 is 48. Find the value of the positive constant p. [3] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2019 9709/13/O/N/19 7 19 @ A 1 a 5 The coefficient of in the expansion of 2x + 2 is 720. x x (a) Find the possible values of the constant a. 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(b) Hence find the coefficient of 1 in the expansion. x7 [2] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2020 9709/12/F/M/20 [Turn over 3 20 @ A @ A 1 5 2 8 1 The coefficient of in the expansion of kx + + 1− is 74. x x x Find the value of the positive constant k. 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over 2 21 @ A 2 6 (a) Find the coefficient of x in the expansion of x − . x 2 [2] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ 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(b) Find the coefficient of x2 in the expansion of 2 + 3x2 x − x [3] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2020 9709/12/M/J/20 5 22 (a) Expand 1 + a5 in ascending powers of a up to and including the term in a3 . 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(b) Hence expand 1 + x + x2 5 in ascending powers of x up to and including the term in x3 , simplifying your answer. [3] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2020 9709/13/M/J/20 [Turn over 6 23 0 a 16 In the expansion of 2x2 + , the coefficients of x6 and x3 are equal. x (a) Find the value of the non-zero constant a. [4] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ 0 a 16 . (b) Find the coefficient of x6 in the expansion of 1 − x3 2x2 + x [1] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2020 9709/11/O/N/20 3 24 The coefficient of x3 in the expansion of 1 + kx 1 − 2x5 is 20. Find the value of the constant k. [4] ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ © UCLES 2020 9709/12/O/N/20 [Turn over 3 25 (a) Find the first three terms in the expansion, in ascending powers of x, of 1 + x5 . 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(b) Find the first three terms in the expansion, in ascending powers of x, of 1 − 2x6 . [2] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ (c) Hence find the coefficient of x2 in the expansion of 1 + x5 1 − 2x6 . [2] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2021 9709/12/F/M/21 [Turn over 4 26 (a) Find the first three terms in the expansion of 3 − 2x5 in ascending powers of x. 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(b) Hence find the coefficient of x2 in the expansion of 4 + x2 3 − 2x5 . [3] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2021 9709/11/M/J/21 5 27 @ A 10 3 1 The coefficient of x in the expansion of 4x + is p. The coefficient of in the expansion of x x @ A5 k 2x + 2 is q. x Given that p = 6q, find the possible values of k. [5] ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ ................................................................................................................................................................ © UCLES 2021 9709/12/M/J/21 [Turn over 9 28 (a) Write down the first four terms of the expansion, in ascending powers of x, of a − x6 . [2] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ @ 2 (b) Given that the coefficient of x in the expansion of 1 + ax the possible values of the constant a. 2 A a − x6 is −20, find in exact form [5] ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ ........................................................................................................................................................ © UCLES 2021 9709/13/M/J/21 [Turn over